1. Technical Field
The present application relates to a condensate drain trap for an air conditioning system.
2. Background Information
In the operation of a typical air conditioning or refrigeration system, moisture from the air is condensed on an evaporator coil and accumulates in a drain pan situated below the coil. A typical drain pan has a tube or threaded connection for connecting an external pipe to carry the water to a safe location for disposal. Air is drawn over the evaporator coil by a blower which causes a negative pressure in the blower compartment, where the drain pan is located. Air conditioning manufacturers specify installing a U-shaped drain trap in the drain line to balance atmospheric pressure with the negative pressure in the drain pan. Condensate water will not drain from the drain pan unless this U-shaped drain trap is installed in the drain line. However, this system has inherent problems. The U-shaped drain trap must be or should be primed before water can flow out of the drain pan. If the U-shaped drain trap is not primed, the velocity of the air blows condensate into the interior of the blower compartment causing corrosion and algae to form. Other problems with the U-shaped drain trap is it, by nature of its design, traps dirt and algae, eventually blocking the flow of condensate. In the winter season, water in the U-tube freezes and cracks, damaging the trap.